Getting into volunteer EMS in Houston

I moved to Houston about 2 years ago. Prior to that, I was involved with a volunteer squad in Virginia for 5.5 years, most of the time as an EMT-I. I stopped running EMS when I moved to Texas. That was mostly because I had no time to do it, but also because of the drop in skill level that I would have had to take going from an I-99 state to an I-85 state.

I will have more time starting in a few months, and I am thinking strongly about getting back into EMS. It would definitely be as a volunteer, as I am a graduate student and that requires as much if not more time than a full-time job.

So with that in mind I have several questions to start off.

I need to find a good volunteer EMS agency. I want to run calls, so it should be relatively busy. I live inside the loop in Houston, but do not mind driving 30-45 minutes for a good agency. A department that would be willing to pay for me to get training in return for a volunteer commitment would also be appreciated, and also leads me to my second question.

My EMT-I has expired since I got out of EMS but my Virginia EMT-B cert is still good for a couple of years; I have never been NREMT certified at any level. I think I am eligible for reciprocity in Texas, but I am not sure. Does anybody know the process for getting reciprocity in Texas?

Also, I want to be able to practice as a medic, so I am looking for a paramedic class in the Houston area. It would need to be evenings and/or weekends to work with my schedule.